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991.
PURPOSE: To determine the clinical utility of the intraocular videoendoscope for evaluation of the ciliary body in eyes with hypotony and as a visualization tool for surgery of the ciliary body. METHOD: A gradient index of refraction rod endoscope was used to evaluate the ciliary body in 14 patients. Videotapes and charts were reviewed retrospectively to correlate the appearance of the ciliary body and to analyze the clinical findings and surgical results. Videoendoscopic surgery to remove fibrous tissue from the ciliary processes was performed in nine eyes. RESULTS: The endoscope produced a clear detailed image of the ciliary body in a state that is undisturbed by scleral depression or other forms of mechanical distortion. In eyes without hypotony the normal ciliary processes are uniformly pigmented with a velvet-like surface at high magnification. White surface changes in the peak and crest of individual ciliary processes (white-caps) were seen in 11 of 14 patients with hypotony. At high magnification the white surface changes had a brush-like texture integral to the ciliary processes. Other findings in hypotony were fibrous covering of the ciliary body in 10 patients, loss of pigment epithelium in 5, traction elongation of the ciliary processes in 8, vascular loops in 4, pigmented sheets in 3, and areas of missing ciliary processes in 1. White caps were present in seven of the nine patients who had surgery for fibrous traction of the ciliary processes and hypotony and three patients with hypotony not due to other endoscopically visible abnormalities of the ciliary processes. Endoscopically visualized dissection of ciliary body in 9 patients resulted in normal or elevated tension immediately postoperatively in 7 (78%). At the most recent visit only three of the patients had normal tension, but for these nine patients the pressures were marginally, significantly (P = 0.08) higher compared to the preoperative pressures. CONCLUSION: The evaluation and management of hypotony is enhanced by the use of intraocular videoendoscopy. Clinical findings of whitecaps and traction elongation of the ciliary processes were associated with ocular hypotony. The endoscope facilitated surgery for dissection and removal of fibrous tissue over the ciliary processes. Further studies are needed to better understand the pathophysiology of ocular hypotony.  相似文献   
992.
Objective To examine the release of counterregulatory hormones and consecutive glimepiride serum concentrations during severe hypoglycaemia (SH) associated with glimepiride therapy.Methods In nine type-2 diabetic patients [age 81±9 (65–93) years; diabetes duration 9±4 (3–15) years; initial blood glucose 33±16 (10–54) mg/dl (1.8±0.9 mmol/l); HbA1c 7.2±1.1 (5.6–8.7)%; creatinine clearance 49±33 (15–107) ml/min] who experienced SH associated with glimepiride therapy with neuroglucopenic presentation, insulin, C-peptide, glucagon, epinephrine, norepinephrine, cortisol, adenocorticotrophic hormone (ACTH), human growth hormone (HGH) and pancreatic polypeptide (PP) were determined in blood samples taken at 4-h intervals prior to and during treatment with glucose i.v. Serum from the same samples was screened for sulphonylurea-type oral antidiabetics. Glimepiride concentrations were determined by a validated atmospheric pressure chemical ionization liquid chromatographic-mass spectrometry (APCI-LC-MS) assay.Results Once treatment had begun, normoglycaemia was maintained; most glimepiride levels were below the limit of detection (LOD <0.01 mg/l) and further sulphonylureas could be excluded. The secretion of glucagon and epinephrine as counterregulatory hormonal responses was unaffected. In addition, protracted marked increases of cortisol and norepinephrine levels were demonstrated. Protracted stimulation of insulin and C-peptide occurred in a period of up to 24 h after SH. No significant protracted responses were observed for ACTH, HGH or PP.Conclusion In SH associated with glimepiride therapy, no correlation between glimepiride serum concentrations and the protracted stimulation of insulin and C-peptide was observed. The secretion of glucagon and epinephrine as counterregulatory hormonal responses was unaffected. Protracted increased release of cortisol might be a medium-term indicator of glimepiride-associated SH.  相似文献   
993.
Percutaneous sclerotherapy under fluoroscopic guidance can be used to treat venous malformations, in order to reduce the lesion's size and associated pain, to improve fonctional impairment or esthetic prejudice. Although this treatment modality seems to be simple, a multidisciplinary approach and rigorous technique is required to avoid serious complications. Technical details, the various sclerosing agents, possible complications and results are reviewed.  相似文献   
994.

Introduction  

The potential of applying data analysis tools to microarray data for diagnosis and prognosis is illustrated on the recent breast cancer dataset of van 't Veer and coworkers. We re-examine that dataset using the novel technique of logical analysis of data (LAD), with the double objective of discovering patterns characteristic for cases with good or poor outcome, using them for accurate and justifiable predictions; and deriving novel information about the role of genes, the existence of special classes of cases, and other factors.  相似文献   
995.
INTRODUCTION: We present the results of a two-experiment study designed to evaluate the neurocognitive and psychological effects of six-degree head-down bedrest and pharmacologic interventions (3,5,3'-triiodothyronine; T3) implemented to enhance the muscle and bone atrophy associated with simulated microgravity. Subsequently, the effects of countermeasures (alendronate and testosterone) administered to retard or reverse these T3 plus bedrest enhanced atrophic changes, were evaluated. Each participant was tested weekly for 5 weeks during Bedrest or non-bedrest (Up) conditions with the Neurobehavioral Evaluation System 2 (NES2), the Symptom Check List 90 Revised (SCL-90-R), and the Coping Responses Inventory (CRI). Resultant data were subjected to repeated measures, between groups analysis of variance testing for all 82 neurocognitive and psychological test measures. RESULTS: In Experiment 1, participants in the Placebo-Bedrest condition performed better on several neurocognitive measures compared to participants in the T3-Up condition. However, participants in the Placebo-Bedrest condition also reported more confusion. In Experiment 2 (countermeasure trials), superior coordination was observed for participants in the Testosterone-T3 condition over those in the Alendronate-T3 condition, but just the opposite for reaction time. Also, testosterone and to a lesser degree, alendronate, were associated with less self-reported emotional distress than T3 plus bedrest alone. CONCLUSION: Triiodothyronine, alendronate, and testosterone each influence participant response to simulated microgravity. Between group differences for significant findings were substantial and averaged 1.62 standard deviations. Although the observed neurocognitive effects likely pose no immediate danger for research participants, the significantly greater level of self-reported psychological symptoms by T3-Placebo and Placebo-Bedrest treated participants is of clinical importance.  相似文献   
996.
997.
Lung involvement in scleroderma   总被引:3,自引:0,他引:3  
Lung involvement (LI) was studied by lung function (LF) in 101 scleroderma patients (circumscribed scleroderma, n = 17; progressive systemic scleroderma [PSS], n = 84; with the subtypes I, acroscleroderma [n = 19]; 2, proximal ascending scleroderma [n = 61]; 3, trunk scleroderma [n = 4]). Eighteen percent of morphea, 32 percent of type 1, 56 percent of type 2, and 75 percent of type 3 patients had impaired LF. The LI was more frequent (57 percent vs 45 percent) and more severe (20 percent vs 3 percent) in PSS with systemic inflammation (form A) compared to those without (form B). Elevated lymphocytes/neutrophils in bronchoalveolar lavage (BAL) were found associated with form A and severe LI. The LF of patients showing an inflammatory cell pattern in initial BAL (n = 3) worsened, whereas those with normal BAL findings (n = 4) did not. Collagenase activity in BAL was significantly elevated in those with elevated lymphocytes/neutrophils in lavage. Patients with type 2 or 3 of PSS, especially form A, carry a higher risk of developing severe LI than circumscribed scleroderma, type 1, or form B patients. Differential cell count and collagenase activity in BAL is correlated with active disease and provides prognostic information.  相似文献   
998.
A method is described which makes the detection of alterations in the pharmacokinetic profile possible when substances are administered during long-term toxicity tests. By superposition of a radioactive dose at the end of the toxicity study a blood level can be obtained which--on the assumption of first-order kinetics--is comparable to that after a single radioactive dose in controls. Differences between blood levels of pretreated and control animals may indicate enzyme induction or damage of the elimination organs, etc., even when morphological changes are evident.  相似文献   
999.
1000.
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